Hard to say without reads, he might raise a worse Ax or a flushdraw depending on his tendencies and how he perceives your c-bet into 3 players. I doubt he's bluffing ever.

If you know he's bad enough to stack off with a worse top pair or with a flushdraw here then 3betting is fine. If you don't and he looks like a tag, you're probably better off either bet/calling the flop and check/folding the turn or simply folding to his flop raise, as 3betting right there will often isolate you against sets only against most players.

Please hide the results next time and try to say something useful about your opponent, like some stats if you have them or simply if he's playing a lot of hands, almost no hands at all, if you've seen him make some weird plays, things like that to help us help you